The Leica TCS SP8-STED is a laser (point) scanning confocal microscope that enables imaging of transparent, medium thick samples via optical sectioning. Specimens/objects of interest should be fluorescently labelled for image acquisition.
This microscopes is equipped with two special modules. The STED (Stimulated Emission Depletion) modules offers spatial super-resolution fluorescence imaging by using a second, high power depletion laser at 592 nm that illuminates the sample in a doughnut shape volume. For conventional light microscopes, the spatial resolution is diffraction limited. Depending on the numerical aperture of the objective (NA) in use and on the wavelength (l) of the light, the resolving power of a light microscope is defined by Abbe’s law: d = 0.5 λ/NA, and cannot be better than ~220nm.
STED, as a super-resolution technique provides resolution down to ~50 nm.
Labelling protocols should be adapted to the existing laser lines that can excite the reporter dye molecules or fluorescent proteins. For super-resolution imaging, please refer to the brochure “The Guide to STED Sample Preparation”.
The second special module of the system enables fluorescence lifetime imaging (FLIM). The electronics and the software module are from PicoQuant (Germany).